4mm-12mm Polycarbonate Greenhouse Sheet Flower Gardens PC Twin Wall Hollow Sheet

The ventilation design of polycarbonate greenhouses should consider the following climatic factors:

temperature

Seasonal changes: The outdoor temperature varies greatly in different seasons. During high temperatures in summer, it is necessary to effectively reduce the temperature inside the greenhouse through ventilation to prevent plants from being affected by high temperatures. For example, larger ventilation openings can be set up or mechanical ventilation can be used to assist natural ventilation. During low temperatures in winter, ventilation should also take into account insulation to prevent a large amount of cold air from entering and causing plants to freeze. This can be achieved by controlling the size and duration of ventilation openings and coordinating with insulation measures.

Day night temperature difference: In areas with a large temperature difference between day and night, ventilation and heat dissipation should be carried out during the day, and ventilation should be reduced appropriately at night to maintain indoor temperature, which is beneficial for plant growth and nutrient accumulation. For example, in autumn, when the temperature is high during the day, open the ventilation opening to cool down, and close the ventilation opening in a timely manner to keep warm after the temperature drops at night.

humidity

Air humidity: Air humidity can affect the transpiration of plants and the probability of disease and pest occurrence. High humidity environments can easily cause diseases and pests, and it is necessary to strengthen ventilation to reduce humidity. For example, during the rainy season or high temperature and humidity periods in summer, increase ventilation volume and duration, promote indoor and outdoor air exchange, and reduce air humidity. In low humidity areas, ventilation design should consider to avoid excessive ventilation leading to water shortage of plants. Humidity sensors can be installed to control the ventilation system according to humidity data, and at the same time, spray and other measures can be taken to increase air humidity.

Precipitation situation: In areas with high precipitation, it is necessary to prevent rainwater from flowing back into the greenhouse. Ventilation openings should be equipped with rain blocking facilities, such as rain covers and canopies. At the same time, ventilation design should consider timely ventilation after rain to reduce indoor humidity and minimize the occurrence of diseases. In arid and rainless areas, ventilation systems can be combined with irrigation systems to promote plant transpiration and improve water use efficiency through ventilation.

wind speed and direction

Average wind speed: In areas with high average wind speeds, the setting of greenhouse ventilation openings should consider wind resistance. Smaller and more numerous ventilation openings can be used to avoid damage to large ventilation openings during strong winds. At the same time, it is necessary to strengthen the stability of the greenhouse structure to prevent it from being blown down by strong winds. For areas with low wind speeds, the ventilation area can be appropriately increased to improve ventilation effectiveness.

Dominant wind direction: Set the position of ventilation openings according to the local dominant wind direction, such as using the windward side ventilation opening as the inlet and the leeward side ventilation opening as the outlet, to promote the formation of good ventilation in the greenhouse and improve ventilation efficiency. For example, in northern China, there is often northwest wind in winter. The southeast side of the greenhouse can be set as the air inlet and the northwest side as the air outlet to reduce the direct blowing of cold air into the greenhouse.

light

Light intensity: Excessive light intensity can cause a rapid increase in indoor temperature, requiring ventilation and heat dissipation. At the same time, shading measures such as sunshade nets and blinds can be combined to reduce light intensity and indoor temperature. In seasons or areas with insufficient lighting, ventilation design should avoid affecting indoor lighting. It is recommended to ventilate during periods of weak lighting or use ventilation cover materials with good transparency.

Sunshine duration: In areas with long sunshine hours, there is more heat accumulation in the greenhouse. The ventilation system should be able to effectively dissipate heat and maintain a suitable indoor temperature. For areas with short sunshine hours, ventilation design should be combined with supplementary lighting measures to ensure ventilation while meeting the lighting needs of plants.